This invention relates generally to data storage devices that include patterned media, wherein each data bit is stored in a magnetically isolated block on the media, and more particularly to a method and apparatus for converting timing errors into symbol errors to manage write mis-synchronization in bit-patterned media recording systems.
Magnetic recording hard disc drives with bit-patterned magnetic recording media have been proposed to increase data density. In patterned media, the magnetic material on the disc is patterned into small isolated blocks or islands such that there is a single magnetic domain in each island or “bit”.
In a bit-patterned media (BPM) magnetic storage system, the loss of write synchronization can introduce catastrophic errors and render the system useless. If the write head clock is not perfectly aligned with the bit islands, bit insertions or deletions can occur during the writing process. Existing error correction code (ECC) schemes and read channel architectures in a magnetic storage system are designed to only correct substitution errors. Hence, even a single insertion or deletion can result in a catastrophic propagation of bit errors in the system as interpreted by these read channel architectures.